Wireless Network Administration: Understanding Range

The maximum range of an 802.11g wireless device indoors is about 300 feet. This can have an interesting effect when you get a bunch of wireless computers together — such that some of them are in range of each other, but others are not.

For example, suppose that Wally, Ward, and the Beaver all have wireless notebooks. Wally’s computer is 200 feet away from Ward’s computer, and Ward’s computer is 200 feet away from Beaver’s in the opposite direction. In this case, Ward is able to access both Wally’s computer and Beaver’s computer. But Wally can access only Ward’s computer, and Beaver can access only Ward’s computer.

In other words, Wally and Beaver won’t be able to access each other’s computers because they’re outside of the 300-feet range limit. (This is starting to sound suspiciously like an algebra problem. Now suppose that Wally starts walking toward Ward at 2 miles per hour, and Beaver starts running toward Ward at 4 miles per hour. . . .)

image0.jpg

Although the normal range for 802.11g is 300 feet, the range may be less in actual practice. Obstacles such as solid walls, bad weather, cordless phones, microwave ovens, backyard nuclear reactors, and so on can all conspire together to reduce the effective range of a wireless adapter. If you’re having trouble connecting to the network, sometimes just adjusting the antenna helps.

Also, wireless networks tend to slow down when the distance increases. 802.11g network devices claim to operate at 54 Mbps, but they usually achieve that speed only at ranges of 100 feet or less. At 300 feet, they often slow down to a crawl. You should also realize that when you’re at the edge of the wireless device’s range, you’re more likely to suddenly lose your connection due to bad weather.